Role of phytase supplementation in improving nutrient digestibility and growth performance for Labeo rohita fingerlings fed on canola meal-based diet

Abstract

The present feeding trial was conducted to assess the optimal level of phytase supplementation required for maximum nutrient absorption and growth performance of Labeo rohita fingerlings fed canola mealbased diet. A standard diet having 30.21% protein and an energy value of 4.26 kcalg−1 was used as reference diet. The experimental diet having similar protein and caloric density was formulated by using 70% reference diet and 30% of canola meal as test ingredient. This experimental diet was then divided into seven test diets and were supplemented by graded levels (0, 250, 500, 750, 1000, 1250 and 1500 FTU kg−1) of phytase enzyme. Chromic oxide was used in reference and test diets as an inert marker. Results showed that phytase supplementation at 750 FTU kg−1 level effectively increased apparent digestibility coefficients of crude protein (64%), crude fat (76%) and gross energy (68%) as compared to reference and other phytase-supplemented diets. The results of present study showed increased growth and feed performance of fingerlings in response to phytase supplementation. Maximum performance was obtained by the fish fed on test diet having 750 FTU kg−1 level. It was concluded that 750 FTU kg−1 level of phytase supplementation in canola meal-based diet is sufficient for increasing nutrient digestibility and growth performance of L. rohita fingerlings.